The service for determining from which number a client has called. This helps to decide how to answer on the incoming call. A telephone company sends DNIS number to the telephone client’s system during establishing connection. As a rule, DNIS number consists from 4 to 10 digits.
IDC projected over 9 billion minutes of voice traffic to travel over worldwide packet networks in 2000, exceeding 135 billion minutes in 2004. Service revenue is projected at 1.6 billion in 2000 and 18.7 billion in 2004.